Add 21/10 and 28/20
1st number: 2 1/10, 2nd number: 1 8/20
21/10 + 28/20 is 7/2.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 10 and 20 is 20
Next, find the equivalent fraction of both fractional numbers with denominator 20 - For the 1st fraction, since 10 × 2 = 20,
21/10 = 21 × 2/10 × 2 = 42/20 - Likewise, for the 2nd fraction, since 20 × 1 = 20,
28/20 = 28 × 1/20 × 1 = 28/20 - Add the two like fractions:
42/20 + 28/20 = 42 + 28/20 = 70/20 - 70/20 simplified gives 7/2
- So, 21/10 + 28/20 = 7/2
In mixed form: 31/2
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